Abstract —Analysis of zircons from Early Paleozoic calc-alkaline granitoids in the central part of the Angara–Vitim Batholith revealed two geochemically different zircon varieties. Central unaltered domains have homogenous BSE images, “magmatic” REE distribution pattern, and the moderate content of trace elements. Altered zones of zircon are characterized by more gentle patterns owing to the growth of LREE and MREE, as well as by the elevated contents of U, Th, Ca, Sr, and Ba. Such compositional peculiarity could be related to the influx of fluid, which caused a metasomatic alteration of granites during their microclinization. Geochemical features of zircons, together with their internal structure, should be taken into account during geochronological study of zircon.

中文翻译：

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Angara-Vitim 基岩早古生代花岗岩中锆石的微量元素地球化学

摘要——对 Angara-Vitim 基岩中部早古生代钙碱性花岗岩中锆石的分析揭示了两种地球化学性质不同的锆石品种。中央未改变区域具有均匀的 BSE 图像、“岩浆”稀土分布模式和中等含量的微量元素。由于 LREE 和 MREE 的生长，以及 U、Th、Ca、Sr 和 Ba 的含量升高，锆石蚀变带的特征是更柔和的图案。这种成分特性可能与流体的流入有关，流体的流入导致了花岗岩在微倾斜过程中的交代蚀变。在锆石年代学研究中，应考虑锆石的地球化学特征及其内部结构。